News Feature
| February 27, 2017

Arsenic-Immune People May Hold Key To Drinking Water Treatment

Hints about overcoming the threat of arsenic contamination in the water supply may reside in an unexpected place: the human body.

“People in a south American desert have evolved to detoxify potentially deadly arsenic that laces their water supply,” New Scientist recently reported.

The New York Timescalled discoveries around arsenic and evolution “the first documented case of natural selection in humans for a defense against an environmental poison.”

The newspaper laid out why such findings matter today for water pros and public officials:

[Research] shows that toxic chemicals can also drive human evolution. Understanding how it happened may help guide public health measures to reduce the suffering caused by arsenic poisoning, which threatens an estimated 200 million people worldwide. And it can also help scientists understand how we detoxify chemicals like arsenic, a process that is still fairly mysterious.

“If you find a signal of natural selection, then you know this has been a huge issue for human survival in the past,” Dr. Mattias Jakobsson said.

Here’s what the latest research shows: People have survived in Chile’s Atacama desert despite dangerous levels of arsenic contamination in the region. The region has “the highest arsenic levels in the Americas,” according to researchers.

“Could it be that arsenic’s negative effects on human health, such as inducing miscarriages, acted as a natural selection pressure that made this population evolve adaptations to it? A new study suggests this is indeed so,” New Scientist reported.

As Mother Nature Network put it: “While the ability to drink poisonous water might not top the list of many people's most desired super powers, it's a different story for those who live in South America's Atacama Desert, where scant water sources are often tainted with high levels of dangerous arsenic.”

The new research, published in February in the American Journal of Physical Anthropology, focused on "an enzyme called AS3MT" which the body uses to "to incorporate arsenic in two compounds, monomethylarsonic (MMA) acid and dimethylarsinic (DMA) acid. People who metabolise arsenic more efficiently convert more of it into the less toxic, more easily expelled DMA," according to New Scientist.

The research showed that the people living in the desert “had a significantly higher percentage of DMA-producing variants of AS3MT than other populations,” Mother Nature Network reported.

The researchers summed up their findings like this: “Our data suggest that a high arsenic metabolization capacity has been selected as an adaptive mechanism in these populations in order to survive in an arsenic-laden environment.”